This invention relates generally to a method and apparatus for screening documents, and has application to a method and apparatus for screening bank notes for defects to determine their suitability for dispensing by automated teller machines (ATMs).
In the course of circulation, bank notes may acquire defects such as holes and tears and, as such defects accumulate, a point is reached when a note becomes unsuitable for dispensing to bank customers by an ATM. It is accordingly common practice to employ bank note screening apparatus to test bank notes for defects prior to loading into a storage cassette of an ATM for subsequent dispensing. Also some ATMs are equipped with screening devices which test deposited notes for suitability for further circulation.
Known bank note screening systems, such as that disclosed in U.S. Pat. No. 4,984,280, include a scanner, typically employing photoelectric detection of transmitted light, for determining the condition of a note. A disadvantage of known systems of this kind is that they do not specifically determine the suitability of bank notes for handling by the cash dispensing mechanism of an ATM.